Sheet feeding mechanism



June 12, 1945'- w. F. LEONHART 7 2,378,306

SHEET FEEDING MECHANISM 2 Sheets-Sheet 1 Filed April 12. 1943 a5 swamton IVi'lZ mm rzeonhai-c,

June 1945. w E LEONHART 2,378,306

SHEET FEEDING MECHANISM Filed April 12, 1943 2 Sheets-Sheet 2 p 74-fiz/t 16 7 5.5

j M MM l'fijlliam ITLeon/rarl,

Patented June 12, 1945 SHEET FEEDING MECHANISM E William F. Leonhart,Mount Lebanon, Pa., assignor, by mesne assignments, to Continental CanCompany, Inc., New York, N. Y., a corporation of New York ApplicationApril 12, 1943, Serial No. 482,721

7' Claims.

My invention relates to mechanism for withdrawing sheets singly and inrapid succession from a stack of the sheetsv and particularly tomechanism by which the sheets are reieasably held at their edges whileindividual sheets are separated from the stack. An object of theinvention is to provide an improvedapparatus by i ing and withdrawingthe can body sheets singly and in succession from the bottom of a stack,and feeding them to the grain breaking mechanism. The b fesentinvention, as illustrated herein, is adapted for use with such a machineand embodies certain improvements on the mechanism shown in said patent,particularly the separators which engage the edges of the lowermostsheets in the stack.

' Other objects of the invention will appear hereinafter. v

Referring to the accompanying drawings:

Figure 1 is a sectional elevation of an apparatus embodying myinvention. I

Fig. 2 is a plan view showing the feeding hopper. a Fig. 3 is afragmentary sectional elevation showing particularly a separator holderand fin-. gers.

Fig. 4 is a view of a separator as indicated by the line 4-4 on Fig. 8.

Fig. 5 is a perspective view of the separator center finger. I

Fig. 6 is a perspective view of the separator double finger.

Referring to the drawings, a stack in of flat sheets I I, as forexample, metal sheets adapted for making can bodies, is supported in afeeding hopper or framework, including horizontal side members I! (Fig.2), cross bars l3 and I3, and vertical corner guides 44. The weight ofthe stack is supported by separator devices I! mounted on the hopperframe.

The sheets II are withdrawn one by one from the bottom of the stack bymeans including suction cups ii. A suction line extending to the cupsincludes a pipe II which opens into a bearing sleeve II in whichreciprocates a vertical tubular shaft II. A crosshead on the upper endof the shaft l9 carries the vacuum cups i6. The'shaft i9 is periodicallyreciprocated by means including a bell crank lev'er 2| connected througha link'22 to a head 23 attached to the'lower end of the shaft Iii. Whenthe shaft is lowered, carrying with it the vacuum cups I 6, a sheet Hiswithdrawn from the stack and disposed on supporting bars 24. The suctionline is cut off and the vacuum released just before the sheet is placedon the plates 24. The sheet is immediately fed forward to the grainbreaker mechanism 25 by means of a kicker arm 26 in the form of a bellcrank fulcrumed on a pivot 2'! and connected through a link 29 to thehead 23.

Reference may be had to the above mentioned Patent 2,235,377, for a moredetailed disclosure of the construction and operation of the parts vabov described.

The sheet separators l5, embodying features of novelty comprisedin thepresent invention will now be described:.

The separators Iii which are mounted on the side bars I2 of the hopper,each comprises a holder adjustable along the bar l2 and held in positionby a face plate 35 and clamping screws 31. The bars l2 and holders 35thereon, are ad- I justed to provide a narrow space between the holderand the edges of the stack. A recess 38 is formed in the face of theholder to receive the separator fingers. These include a separatorcenter finger39 and a double separator finger 40. These fingers arepivotally mounted on a hinge rod 4| secured in the holder. The doublefinger 40 is in the form of a yoke comprising parallel-spaced armsconnected by an integral web 42, the finger 39 being mounted betweensaid arms.

The fingers are adjustably held in position to engage the sheets Hadjacent the lower ends of the stack, by means of upper and loweradjusting screws 43 and 44 (Fig. 3), which respectively engage thecenter finger 39 and the web 42 of the double finger. The finger 39 hasa smooth front face 45 which is downwardly and inwardly inclined, sothat the lower portion of said face engages the edges of the lowersheets ll of the stack.-

The lower portions of the front faces of the double fingers 40 areformed each with a series of minute teeth or ribs extending thereacrossand providing holding surfaces 46 to grip the lowermost sheets of thestack after said sheets have passed below or'out of contact with thesurfaces 45 of the middle fingers. The double fingers 40 are adjusted tobring said holding surfaces 46 in- 2 asvasoe wardly a slight distancebeyond the surfaces ll of the center fingers. The double fingers areformed with their front faces if more or less concave or in the formfofa re-entrant angle to permit the holding surfaces 4| of the center movealong said surfaces, said separator devices fingers to hold the sheetsabove the corrugated surface 40.- As the sheets move downward, the

suction cups l8 reach up periodically and withdraw the lowermost sheetand pull it downward off the separator fingers. 'lhe operation of thesuction cups gives a slight motion to several of the lowermost sheets ofthe pack. The toothed forwardly and inwardly inclined relative to thedirection in which the sheets are withdrawn, and spaced to cause thesheets to be bowed as they including corrugated holding surfacespositioned beyond said inclined surfaces in the direction of movement ofthe sheets and in position to engage surfaces 48 operate by a scrapingaction to slight- I 1y separate the edges of the lowermost sheets andprevent more than one from being withdrawn from the stack at one time.when more than one sheet is initially pulledloose by the suction cups,the extra sheets remain supported at some point on the toothed surfacesuntil subsequent downward strokes of the suction cups withdraw themsingly from thestack. It, will be seen that the toothed fingers functionchiefiy to separate the sheets and to assure their being withdrawn andfed singly. while the weight of the stack or center fingers. As shown inFig. 1, the'end frame members it and Il are provided with recessesbody-of sheets is carried mainly by the smooth the edges of the sheetsand hold them separated,

and means for adjusting said corrugated surfaces relative to saidholding surfaces in directions toward and from the sheets at 'saidend ofthe stack 3. Sheet feeding mechanism comprising a separator forseparating the edges of the sheets in a stack and holding said edgeswhile the sheets are withdrawn from the stack, vsaid separatorcomprising a holder, a finger pivoted in said holder and having a sheetengaging surface, and

a second finger pivoted in said holder and having a fine-toothed surfacepositioned adiacent to and extending beyond said first mentionedsurface.

I 4. Sheet feeding mechanism comprising a seD- arator for separating theedges'of the sheets in a stack and holding said edges while the sheetsare withdrawn from the stack. said separator ,comprising a holder, acenter finger mounted in' said holder and having a surface for engagingthe edges of the sheets, and a double separator finger mounted in saidholder and havingytcothed surfaces at opposite sides of said centerfinger, said toothed surfaces being positioned beyond said firstmentioned surface in the direction of movement of thesheets.

5. A separator comprising a'kholder, a center finger, and a doublefinger, said fingers being 30 in which separator fingers are mounted inpo--" sitlon to engage the end edges of the sheets and operate in thesame manner as the fingers rnouicitlid in the holderslin spiritandscopeofmyinventicn.

I claim: 1. The combination 'of means for holding a stack of flatsheets, means for withdrawing said sheets singly and in succession fromone end of the stack in a direction perpendicular to the sheets. aholding device having a holding surface positioned and arranged toengage the edges of the sheets adjacent said end, of the stack, saidsurface being inwardly inclined to project into the path of" the sheetsand cause-them "to be bowed as they approach the position'to bewithdrawn from the stack; a separator finger sever. rate from saidholding device and having a toothed surface positioned to engage, saidedges of the sheets as they move beyondsaid inclined surface and holds'aid edges separated ,to prevent more than one sheet at a'time'beingwithdrawn from the stack, and means for separately adjusting saidholding device and said separator finger each toward and from the pathof the sheets.

2.- Sheet feeding mechanism comprising means for holding a stack of fiatsheets, means for withdrawing said sheets singly and in succession fromone end of the stack in a direction normal to said sheets, and separatordevices positioned at opposite sides of the stack adjacent said endthereof, said devices comprising holding surfaces pivoted in'sa'idholder to swing about the same axis, said double finger comprising apair of arms between which said center finger is pivoted, said I doublefinger having toothed surfaces. M 4o 6-. In an apparatus for withdrawingsheets Modifications may be resorted to within the singly and insuccession from the bottom of a stack of said sheets, a separatorcomprising a holder formed with a recess in one face thereof, a pivotrod mounted in the said recess, and separator fingers positioned withinsaid recess and pivoted on said rod and depending therefrom, saidfingers including a finger having a surface positioned and arranged toengage the edges of the lower sheets in said stack and forming asupport-for said sheets, and a second finger having a toothed surfaceextending below said support- .ing surface of the first'finger.

'7. In an apparatus for withdrawing sheets singly and ,in successionfrom the bottom of a stack ofsaid sheets,a separator comprising a holderformed with a recess in one face thereof,

a pivot rod mounted in the said recess,'and separator fingers positionedwithin. said recess and pivoted on said rod and depending therefrom,said separatorfingers. including a center finger and a double finger,the latter having spaced arms between which the center finger ismounted, said center finger having an inclined surface to engage theedges of the sheets in said stack and said double finger having toothedsheet-engaging surfaces on opposite side of and below said inclinedsurface.

WILLIAM F. LEONHART.

